To provide a fine structure measurement method and a fine structure measurement apparatus allowing to evaluate the shape of a fine structure formed on the surface of a semiconductor substrate nondestructively, easily, with high precision, and quantitatively.

A reflection spectrum for a sample of which the dimensions of the fine structure to be measured are known is measured (A1). A characteristic of the reflection spectrum (a waveform parameter) having a strong correlation with the measured dimensions of the fine structure is determined (A2). The relationship between the dimensions of the fine structure and the waveform parameter is determined (A3). Using the relationship, the dimensions of a fine structure are determined from a reflection spectrum for the fine structure with unknown dimensions (A4, A5).